Software update stalls with 15 minutes to go.

Hi BobC32,

We see you're having an issue with installing the macOS Big Sur update, and we'd be happy to help.

While it may note an approximate time, it may take longer than it mentions. How long have you been able to leave it at that part in the process? In particular, have you been able to try letting it try and complete the update process overnight?

If it hasn't provided any errors, it's possible that it's still working on completing the update.

However, be sure to rule out anything that may be interfering with the download. This can include disabling any VPNs, networking software, security software, etc.

You may also try setting up a new temporary Admin user on the Mac, switch over to that, and then try completing it on that fresh user account: Set up users, guests, and groups on Mac

Take care.

BobC32,

Excellent, we're happy to hear that the update was able to complete in the end. We hope you have a great rest of your day.

Cheers.